/*
 * Copyright 2010 Askar Kalykov, oxygene.core@gmail.com
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

package com.oxygenecore.processor.expression;

import com.oxygenecore.processor.CalculationException;
import com.oxygenecore.processor.LeafExpression;
import com.oxygenecore.processor.ExecutionContext;

/**
 * @author Askar Kalykov
 *         Date: 11.09.2010
 *         Time: 15:25:24
 */
public class VariableValue<T> implements LeafExpression<T> {

    private String name;

    public VariableValue(String name) {
        if (name == null){
            throw new NullPointerException("name");
        }
        this.name = name;
    }

    public String getName(){
        return name;
    }

    public T getValue(ExecutionContext executionContext) throws CalculationException {
        try{
            return (T)(executionContext.getVariable(name)).getValue();
        } catch( ClassCastException e){
            throw new CalculationException(e);
        }
    }
}
